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--- tailorcrete:input_file_description [2012/06/21 10:58] – kolarfil
+++ tailorcrete:input_file_description [2012/09/13 16:29] (current) – bp
@@ Line 1: / Line 1: @@
-=== Input File Description ===
+==== Input File Description ====
-Here, general description of OOFEM input files for solving flow problems can be found. Fully general description of OOFEM input file (for all problems) can be found here: [[http://www.oofem.org|www.oofem.org]]
+Here, a description of OOFEM input files related to flow problems, can be found. The complete and general description of OOFEM input format (for all problems) can be found here: [[http://www.oofem.org|www.oofem.org]]
 As a sample input file, input file for V-funnel simulation is choosen:
-{{:tailorcrete:vfunnel_tau60_mu20_beta0.2_oofem.in|}}
+{{:tailorcrete:vfunnel_tau40_mu20_beta0.2_oofem.in|}}
-In general, OOFEM input file can be (imaginary) divided into three main sections. In the first section specifications about type of problem under consideration, type of solver and exported variables are specified. In the second section there is a mesh descriptions. That means list of nodes with its numbers, coordinates and boundary conditions and list of elements specifying its type, numbers of connecting nodes, it's appropriate material and eventually its load. In the third section description of materials, boundary conditions and related entities is done.
+In general, OOFEM input file can be (imaginary) divided into three main sections. In the first section specifications about type of problem solved, including specification of type of solver and exported variables, are to be provided.
+In the second section, the computational mesh is specified. This includes specification of nodes (with associated coordinates and boundary conditions) and specification of individual elements (with their type, nodal connectivity, materials and eventually applied loadings).
+In the third section, description of material models, initial and boundary conditions is done.
-  * **First section**
- In first section (first seven lines), there is description of type of problem under consideration, type of solver and exported variables are specified.
-First line specifies the location of OOFEM output file. Note, that the path must be an absolute path.
-Second line is for user comment. There can be any description of solved problem, OOFEM ignores that line.
+===First section===
+ In the first section (consisting of the first seven lines), the specifications related to type of problem solved, type of solver and exported variables are provided.
-Third line describes type of solver and it's parameters. Some of them are genereal and necessary for all solvers, some of them are specific for concrete solver.
+The first line specifies the path to output file containing textual output with simulation results.
-Note, that order of keywords is not determined!!!
+The second line is intended to name the simulation. It can contain any description of solved problem, OOFEM ignores that line.
+The third line describes type of problem, its parameters, and numerical solver. Note, that the order of keyword-value pairs is optional !!
-^  Parameter   ^  Possible values   ^   Description of function   ^
+^  Keyword   ^  Possible values   ^   Description of function   ^
 |  supg  |   -   | The type of solved problem/type of solving (numerical) scheme. Here, **//supg//** represents name of solver for incompressible Navier-Stokes equations. It is a fully stabilized numerical scheme with Stramline-Upwind/Petrov-Galerkin and Pressure-Stabilizing/Petrov-Galerkin stabilizations. |
 |  nsteps  |  integer number  | Number of time steps.|
@@ Line 44: / Line 45: @@
-  * ** Second section **
+===Second section ===
 In the second section mesh geometry is specified. In first line of second section (globally counting it is 8. line) number of mesh entities (elements, nodes...) and other items.
-^  Parameter   ^  Possible values   ^   Description of function   ^
+^  Keyword   ^  Possible values   ^   Description of function   ^
 |  ndofman  |  integer number  |Number of mesh nodes|
 |  nelem  |  integer number  | Number of elements in the mesh|
@@ Line 61: / Line 63: @@
 **node:** node 1 coords 3 2.250000e+02 0.000000e+00 0.000000e+00 bc 3 1 4 0
-^  Parameter   ^  Possible values   ^   Description of function   ^
+^  Keyword   ^  Possible values   ^   Description of function   ^
 |  node  |  integer number  |Serial number of the node.|
 |  coords  |  vector valued  |Coordinates of the node. It is a vector, first number determines number of columns, the rest are x,y,z coordinates.|
 |  bc  |  vector valued  |Boundary condition corresponding to the node. Again, first number determines number of columns, the rest specifies concrete choice of BC for each degree of freedom.|
+Similarly for the elements:
+**element:** tr1supg 1 nodes 3 9 41 340 crosssect 1 mat 1 bodyloads 1 3 boundaryLoads 2 5 1
+^  Keyword   ^  Possible values   ^   Description of function   ^
+|  tr1supg  |  integer number  |It is the name of corresponding element and it's number.|
+|  nodes  |  vector valued  |Specification of nodes corresponding to the element.|
+|  crosssect  |  integer number  |Number of crosssection corresponding to the element. It is meaningless in fluid mechanics, so it is empty crosssection all time.|
+|  mat  |  integer number  |Number of material corresponding to the element.|
+|  bodyloads  |  vector valued  |Represents body load acting to the element. First number determines number of columns, rest of the numbers represents corresponding type of body load (specified in third section)|
+|  boundaryLoads  |  vectro valued  | Represents load on the boundary on the element. The rules are the same as for bodyloads.|
+===Third section===
+In the third section, specification of **//crosssections, materials, boundary//** and **//initial conditions//** and **//loadtimefunctions//** is done.
+Since general description of these parameters is little bit complicated, we refer interested reader to [[http://www.oofem.org|www.oofem.org]] for further details. Here, only quick description of lines in presented file will be given.
+^  Entity  ^  parameters in presented file  ^  Description  ^
+|  emptycs  |  1  |Emptycs means "void crosssection". (it has no meaning in fluid dynamics, but it has to be specified)|
+|  twofluidmat  |  1 mat 2 2 3  |Twofluidmat is name of "master material" for two fluid flow. It coordinates compilation of diffusive temrs depending where the gausspoint is (concrete or air). Number "1" means that it is a first material. Parameter **//mat//** is a vector containing numbers of materials governed by twofluidmat (note, that the first number specifies number of columns). Here, Twofluidmat has two "slaves materials with numbers "2" and "3".|
+|  newtonianfluid  |  2 d 0.000001 mu 0.001  |Description of newtonian fluid. It is the second material, **//d//** is density, **//mu//** means viscosity.|
+|  binghamfluid2  |   3 d 0.0000023 mu0 0.02 tau0 0.04 muinf 0.001  |Description of Bingham fluid. It is the third material, **//d//** is for density, **//mu0//** is plastic viscosity and **//tau0//** is yield stress. **//muinf//** is some minimal value of mu due to numerical problems.|
+|  BoundaryCondition  |  1 loadtimefunction 1 prescribedvalue 0.0 valtype 5  | Description of first type of BC (Dirichlet BC). It uses loadtimefunction no. 1 and the prescribed value is 0.0. **//valtype//** is specification of physical meaning of BC. Number "5" means velocity.|
+|  Deadweight  |  3 components 2 0.0 -9810 loadTimeFunction 1 valtype 2  |This is type of body load. It is considered as a boundary condition, so it shares the numbering with previous item. It is the third BC. **//components//** is the body load vector with 2 components (x and z direction).|
+|  ConstantEdgeLoad  |  5 ndofs 2 loadtype 4 loadTimeFunction 1 components 2 0 0 properties 1 a 0.2  |This is specification of boundary load. Numbering is shared with all boundary conditions, this is fifth one. **//ndofs//** must be equal to the number of corresponding dofs, in this case it is 2 (components of velocity). **//loadtype//** specifies type of BC, for example flux, convection, etc. Number "4" means "Slip with friction" boundary condition. **//loadtimefunction//** and **//components//** are the same meaning like before. **//properties//** stores coefficient of friction, here it is equal 0.2|
+|  ConstantFunction  |  1 f(t) 1.0  | Specification od loadtime function. This is just constant function, sine there are BC's not depending on time. It is the first function with value equal to "1" |
+| UsrDefLTF  |  2 f(t) "1-(t>0.04)"  | User defined load time function. It is the second load time function. "1-(t>0.04)" means, that it is active for time greater than 0.04.|